Cubane-like water clusters in a 3D supramolecular network of zinc with pyridine-2,6-dicarboxylic acid and 5-aminotetrazole

The reaction of zinc ions with pyridine-2,6-dicarboxylic acid (H2PDA) and 5-aminotetrazole (HATZ) in hydrothermal condition gives rise to a 2D interdigitated network of composition [Zn2(PDA)(ATZ)2]·4H2O (1). The two independent zinc(II) ions, both located on a crystallographic twofold axis, show a different coordination environment, namely a highly distorted trigonal bipyramidal and a tetrahedral geometry. An octameric cluster of lattice water molecules in the lattice voids produces a 3D supramolecular architecture through hydrogen bonding. Thermogravimetry, infrared spectra, and elemental analysis have also been applied to characterize 1. Fluorescence study indicates the intraligand π–π∗ transition perturbed by the metal ion.